Not executing commands immediately
Its normally a problem with the graphic. Check that your graphics drivers are up to date. Also once you have done and if the problem is still there mess with the windows draw settings in user preferences. The settings under system. 

Also have a look at these links
https://www.blender.org/forum/viewtopic.php?t=26691
https://www.blender.org/forum/viewtopic.php?t=28035